GENERAL SCIENCE REVIEWER1st Quarter 2013-2014

SCIENCE PROCESSES

Observe- to use one or more of the five senses to gather information; different (measuring) tools and equipment are also used to make observations.Qualitative observation- gathering information and/or describing the objects/things using the five senses; description of objects; Ex. The blue book is new and smooth. It is very thick.Quantitative observation- gathering information using measuring tools and equipment; properties that can be measured; Ex. The mass of the book is 100 g. It is 30 cm long and 25cm wide. Collect Data- gathering information about observations and measurements in a systematic way; tables and charts are used to systematically collect dataPredict- to say what is going to happen in the future, often on the basis of present indications or past experienceExperiment- a test, especially a scientific one, carried out in order to discover whether a hypothesis is correct; testing the hypothesisMeasure- something used to figure quantity: something used to determine a quantity; mass, volume, lengthCommunicate- giving or exchanging information verbally, orally/and or in writing; enables an individual to express ideas, feelings and needs to othersInfer- making an early conclusion based on certain observations; to come to a conclusion or form an opinion about something on the basis of evidence or reasoningHypothesize- It is a tentative conclusion or answer to a specific question raised at the beginning of the investigation; educated guess about the answer to a specific question

CLASSIFICATION OF MATTER

Solution- a mixture of two or more components; has 1 color, 1 phase, 1 layer, 1 form all throughout; a solution consists of two

components called the solvent and the solute. Generally, the component present in small amount is called the solute; the solute and the solvent dissolve in each other. Usually the solvent is the component present in greater amount. Ex. sugar solution- sugar is the solute and water is the solventSuspension- a mixture of 2 or more components, has 2 or more phases, 2 or more layers; some particles settled at the bottom, some float Ex. Water and oil, gravel and sandColloid- looks like a solution but the particles are bigger than of the solution, Exhibits Tyndall effect- (scattering of light; scattered particles block the light; beam of light is visible) Ex. Starch solution, paint, paste/glueHomogeneous mixture- a mixture which has only one phase, solution is a homogeneous mixture; Ex. Water and saltHeterogeneous mixture- a mixture which has two or more phases, suspension is a heterogeneous mixture; Ex. Halo-haloSolubility- there is a maximum amount of solute that can dissolve in a given amount of solvent at a certain temperatureSaturated solution- the solution that contains the maximum amount of solute dissolved by a given amount of solvent; if you add more solute to the solvent, it will no longer dissolve. The solution has reached its saturation point; the presence of an excess solid which can no longer dissolve is evidence that the solution is saturatedUnsaturated solution- when it contains less solute than the maximum amount it can dissolve at a given temperature; has not reached the saturation point yetSupersaturated solution- beyond the maximum capacity; very temporary condition, when the solution is heated and cooled or disturbed crystallization may occurConcentration- describes the relative amounts of solute and solvent in a given volume of solutionConcentrated- When there is a large amount of dissolved solute for a certain volume of solvent; more solute less solvent

Dilute- A solution that has a small amount of dissolved solute in comparison to the amount of solvent; more solvent less soluteMixture- combination of two or more components; can be separated by physical means: filtration, evaporation, distillation, decantation, sieving or using magnets; may be solid, liquid or gas; may be homogeneous or heterogeneousPure Substance- a pure form of matter, cannot be divided into simpler form by ordinary means; element and compoundElement- simplest form of matter; indivisible; atom is the smallest unit of elementCompound- combination of two or more elements; can be separated but not by ordinary means; electrolysis (a process to separate the components of water from each other through a passage of electric current) molecule is the smallest unit of a compoundMetal- appears to the left of the dark ziz-zag line on the periodic table. Most metals are solid at room temperature. Luster- Shiny; Ductile- can be drawn into wires like copper; Malleable- can be hammered into thin sheets; Conductor; High Melting point; Dense ; can corrode or form rustNon-Metal- occur to the right of the dark zigzag on the periodic table. Although Hydrogen is in family 1, it is also a nonmetal. Many nonmetals are gases at room temperature; Dull; Brittle; Insulator; Low melting point; Less denseMetalloid- Metalloids can be found clustered around the dark zigzag line that separates metals and non-metals. Metalloids (metal-like) have properties of both metals and nonmetals; solids that can be shiny or dull; conduct electricity and heat better than nonmetals but not as well as metals; malleable and ductilePeriodic Table- it tells about elements; elements are arranged in columns which are called family or group-they have similar properties; elements are also categorized into rows called series or periods- they do not have similar propertiesAcid- Turns blue litmus paper to red; Tastes sour; Corrosive; Harmful or fatal if swallowedStrong irritant to eye, skin and mucous membrane; pH 7 below (Red pH paper- strong acid)

Base- Turns red to blue; Tastes bitter; Slippery; Causes severe eyes and skin damage and burns;Fatal if swallowed; pH 7 above (blue/purple pH paper-strong base)Physical property- Property that can be specified without reference to another substance and that can be measured without causing a chemical changeIntensive property- Properties regardless of the amount; does not depend on the amount of an object, whatever the amount is the property is still the same; Color, Taste Boiling point, Freezing point, Melting point,Density- amount of mass per volume of an object; denser sinks, less dense floats (D = m/v)Extensive property- Properties which depend on the amount of an object; bigger object has bigger amount, smaller object has smaller quantity; Volume, Shape, Size,Diameter, Mass, Length, Height, WeightChemical property- Ability of a substance, either by itself or with other substances to undergo a change into new substancesPhysical Change- changes in the physical appearance only, the composition is still the same, can return to its original state; no new substance is formedChemical Change- Changes in the physical state; cannot return in its original state; new substance is formed; Evidences of chemical change- Change of color; Evolution of smoke/gas; Increase in temperature

Additional Concepts:

Water Displacement method- used to measure the volume of irregular object. The volume of an irregular object is equal to the final volume of the water with the object minus the initial volume of the water without the object. Independent variable- manipulated variable; As the scientist changes the independent variable he observes what happens; variable that affects the dependent variable. Ex. The effect of fertilizer in okra plant. The fertilizer affects the plant.Dependent variable- responding variable; variable that is affected by the dependent variable; the variable that is observed. Scientist

focuses his or her observation on it, to see how it responds to change made to the independent variable. Ex. The effect of fertilizer in okra plant. The okra plant is affected by the fertilizer.Examples:How much water flows-Opening of faucet: independent- amount of water flowing: dependentGrowth of plant

- type of fertilizer: independent- height of the plant : dependent

Controlled variable/Constant- the variable that is the basis of the experiment; something that will always remain the same in your experiment; unchanged Examples:

The plant to be used. (okra plant only)The amount water/ fertilizer. (same amount)

Steps in Scientific Method(Observe)Formulate a problemGather dataHypothesizeTest hypothesis/ExperimentInterpret/analyse dataMake Conclusion(Verification)RecommendationPublish

Good Luck!

Prepared by: Marian Grace C. Toribio General Science Teacher